Anti-sticking sand casting coating and preparation method thereof

Abstract

The invention relates to an anti-sticking sand casting coating and a preparation method thereof, and belongs to the technical field of casting. According to the anti-sticking sand casting coating andthe preparation method thereof, a refractory aggregate is selected, an irreversible phase change is generated at a relatively low temperature and large expansion is generated, so that the surface of powder particles in a coating layer sintering shell is sintered more sufficiently, and the particles are in general adhesion due to surface fusion; the coating layer is in a glassy state, the gap of the coating layer is less, the density is higher, the shielding effects of element migration and diffusion are stronger, high-viscosity square quartz generated during high-temperature transformation canresist permeation of metal liquid, and the defect of mechanical sand sticking of castings can be prevented; and the line shrinkage coefficient differences between the glass state coating layer and the casting metal are also large after cooling, the cutting stress of the interface between the casting and the coating layer is increased, so that the coating layer and the casting are peeled off automatically, so that a casting with a smooth surface is obtained; and the thermal chemical stability of a generated mullite phase is high, the generated mullite phase is not easy to react with acid and alkaline oxides, and the prevention of the chemical sand sticking defects of castings is facilitated.

Description

technical field [0001] The invention relates to an anti-stick sand casting coating and a preparation method thereof, belonging to the technical field of casting. Background technique [0002] Casting coatings are used to apply to the surface of the cavity and core, and are used to improve the erosion resistance of the casting, the fire resistance of the surface, the chemical stability, the performance of resisting sand sticking and the resistance to sticking, etc. It is an indispensable auxiliary material for high-performance casting, which is mainly composed of aggregate, suspending agent, carrier liquid, binder and special additives. In the production of castings, casting coatings play an extremely important role in casting. Before the casting is poured, a layer of paint is applied on the surface of the cavity with a brush, which can effectively prevent some defects such as trachoma, sticky sand and sand inclusions of the casting, effectively improve the surface quality o...

AI Technical Summary

Problems solved by technology

(7) The thermal stability is better. Thermal stability is the property that the coating will not crack due to rapid temperature changes. In casting coatings, the thermal expansion coefficient of quartz powder is large, so the thermal stability of the coating will be reduced.